(a) Technical Field
The present disclosure relates to a prism member, a backlight assembly having the same, and a display device having the same. More particularly, the present disclosure relates to a prism member for further improving the luminance characteristic of passing light, a backlight assembly having the same, and a display device having the same.
(b) Discussion of the Related Art
Among various display devices, a liquid crystal display, which has highly improved performance with the down-sizing and weight reduction due to rapidly developing semiconductor technologies, has become one of several popular display devices.
Since a liquid crystal display has various advantages, such as down-sizing, weight reduction, and low power consumption, a liquid crystal display has gradually attracted attention as a viable display alternative for a conventional cathode ray tube (CRT). Recently, a liquid crystal display has been used as a display device for many other information processing devices that require a display device, such as small-sized products like cellular phones, personal digital assistances (PDAs), and so on, as well as middle/large sized products such as monitors, televisions, and so on.
A conventional liquid crystal display is a non-emissive type of display device in which the alignment of liquid crystal molecules is changed by applying a voltage to specifically align the liquid crystal molecules for displaying images using optical characteristic changes, which are caused by the change of the alignment of the liquid crystal molecules, such as such as birefringence, optical rotary power, dichroism, and optical scattering characteristics.
Since the liquid crystal display uses a non-emissive type of display panel that does not emit light by itself, the liquid crystal display has a backlight assembly for supplying light to a rear surface of the display panel.
The backlight assembly may use a lamp, such as a tube type cold cathode fluorescent lamp (CCFL) or an external electrode fluorescent lamp (EEFL), a planar light source providing uniform light, or a light emitting diode (LED) having a high luminance, as a light source.
In addition, the backlight assembly may include a prism member disposed between the liquid crystal panel and the light source in order to improve luminance characteristics of the light emitted from the light source. The prism member concentrates the light passed therethrough so as to improve luminance, however, a bright line may be generated in the light arriving at the liquid crystal panel after passing through the prism member. The bright line may be prevented from occurring by disposing the light source and the prism member to be spaced apart from each other by an optimal distance at which the bright line cannot be recognized.
The prism member, however, can be deviated from its original position by an external impact or it can be deformed by being bent or twisted by long exposure to high temperature or high humidity. In this case, the prism member may be at least partially spaced apart from the light source by the appropriate distance. Thus, a problem occurs that the bright line is generated in the light arriving at the liquid crystal panel after passing the prism member, and an external quality of the display device may be deteriorated.